(i) Field of the Invention
The present invention relates to a keyboard lid opening and closing mechanism for a keyboard musical instrument.
(ii) Background Art
These days, an operation panel provided in a variety of keyboard musical instruments, such as an electronic piano or an electronic organ, is becoming larger since it is required to arrange a variety of operation elements and indicators on the operation panel to realize a various types of musical performance. Therefore, a keyboard lid for covering such a large operation panel and a keyboard is also required to be accordingly large.
In a conventional keyboard musical instrument, a large keyboard lid covering a keyboard and an operation panel is removed from over the keyboard and the operation panel, and is housed inside the keyboard musical instrument during a musical performance by a player. Usually, removing a keyboard lid covering a keyboard and an operation panel from over the keyboard and the operation panel is referred to as xe2x80x9copening a keyboard lid,xe2x80x9d while covering a keyboard and an operation panel with a keyboard lid is referred to as xe2x80x9cclosing a keyboard lid.xe2x80x9d Therefore, the term xe2x80x9copening and closing of a keyboard lidxe2x80x9d is used herein with the meaning as described above.
When a large keyboard lid as above is formed with a single plate-like member, the depth of the keyboard musical instrument must be large.
Accordingly, in some conventional keyboard musical instruments as mentioned above, the keyboard lid is formed by connecting a plurality of plate-like members, such as a primary lid and a secondary lid, with a hinge or the like, and is folded at the connecting portion so as to be housed inside the keyboard musical instrument, so that the overall size of the keyboard musical instrument may be reduced. For example, the keyboard lid opening and closing mechanism for a keyboard musical instrument disclosed in Publication of Unexamined Japanese Patent Application No. 2001-343976, comprises a retention mechanism provided with a first arm member which is rotatably held by a base fixed to the inside surface of an arm and a second arm member which is rotatably held in a coaxial manner with respect to the first arm member and is designed to operate in conjunction with the first arm member.
The retention mechanism operates as follows. In the opening operation of the keyboard lid, when the keyboard lid is moved to the inside of the body of the keyboard musical instrument, the keyboard lid abuts the first arm member.
When the keyboard lid is further moved, the first arm member is pressed by the keyboard lid and starts rotating. Then, the second arm member starts rotating in conjunction with the first arm member, and the end portion of the second arm member lifts up the keyboard lid from thereunder. As the result of the operation of the second arm member, the keyboard lid is folded at the section connected by the hinge.
When the keyboard lid is further moved, the keyboard lid in the folded state is housed inside the body of the keyboard musical instrument.
However, the above described keyboard lid opening and closing mechanism has a complex structure and requires a large space for installation thereof since the mechanism includes rotating members.
An object of the present invention, which has been made to solve the above problems involved in the prior art, is to provide a keyboard lid opening and closing mechanism for a keyboard musical instrument which has a simple structure and does not require a large space for installation thereof.
The above and other objects are attained by a keyboard lid opening and closing mechanism for a keyboard musical instrument which comprises a keyboard lid including a front lid for covering over a keyboard placed between arms arranged opposite to each other in the vicinity of the front left and right ends of the keyboard musical instrument, and a rear lid having a front end connected with the rear end of the front lid by a connecting portion in a foldable manner into a reverse V-shape, the keyboard lid being movable between a position of covering over the keyboard (lid closed position) and a position of being housed inside the keyboard musical instrument (lid open position); and a keyboard lid guide portion for guiding the keyboard lid between the lid closed position and the lid open position. The keyboard lid opening and closing mechanism further comprises a reverse V-shape forming portion for folding the keyboard lid moving from the lid closed position to the lid open position into a reverse V-shape configuration at the connecting portion, a rotation support portion for supporting the rear lid of the keyboard lid folded into a reverse V-shape configuration at the connecting portion by the reverse V-shape forming portion when the keyboard lid moves from the lid closed position to the lid open position, thereby rotating the rear lid around the support portion, and a keyboard lid stop portion for stopping the keyboard lid while moving in the lid open position.
According to the present keyboard lid opening and closing mechanism for a keyboard musical instrument, the keyboard lid in the lid closed position is moved toward the lid open position to open the keyboard lid covering over the keyboard for a musical performance. Specifically, the keyboard lid is moved toward the inside of the body of the keyboard musical instrument by, for example, pushing the front lid. The keyboard lid is guided by the keyboard lid guide portion between the lid closed position and the lid open position. Then, the keyboard lid while moving is folded into a reverse V-shape configuration at the connecting portion by the reverse V-shape forming portion. In this case, the reverse V-shape forming portion may be disposed at the place through which the undersurface of the keyboard lid while moving passes in a contact manner with the reverse. V-shape forming portion. Subsequently, the rotation support portion supports the rear lid of the keyboard lid folded into a reverse V-shape configuration. Then, the front end of the rear lid is pushed in a different direction from the direction toward the rear end of the rear lid, and the rear lid starts to rotate around the support portion, and thereby the keyboard lid becomes folded further. Finally, the keyboard lid stop portion stops the keyboard lid in the lid open position to house the keyboard lid in the folded state within the body of the keyboard musical instrument. The keyboard lid stop portion is designed to stop the front lid while moving.
On the other hand, to close the keyboard lid after the musical performance, the keyboard lid in the lid open position is moved toward the lid closed position. Specifically, the keyboard lid housed in the folded state inside the body of the keyboard musical instrument is moved toward over the keyboard by, for example, pulling the front lid over the keyboard. Then, the keyboard lid detaches from the keyboard lid stop portion, while the rear lid rotates in the opposite direction to the direction of opening the keyboard lid. During this process, the reverse V-shape formed by the keyboard lid gradually becomes flat. Subsequently, the rear lid detaches the rotation support portion, and the keyboard lid is pulled out from the body of the keyboard musical instrument. Thus, the keyboard lid covers over the keyboard in the lid closed position.
As described above, to house a keyboard lid in the folded state inside the keyboard musical instrument, only the reverse V-shape forming portion, the rotation support portion and the keyboard lid stop portion are necessary. Therefore, the structure of the mechanism for opening and closing the keyboard lid is simplified, and a large space for installation of the mechanism is not necessary since these portions include no movable parts.
A keyboard musical instrument of some type has an inclined operation panel provided obliquely above and behind the keyboard. In such a keyboard musical instrument, the keyboard lid in the lid closed position covers over the operation panel as well as over the keyboard.
The above described keyboard lid guide portion may be designed to guide the rear lid in the obliquely downward direction when the keyboard lid moves from the lid closed position to the lid open position, thereby to enable rotation of the rear lid in a compact space. In this case, the depth of the space for housing the keyboard lid may be reduced compared with the case of guiding the keyboard lid in an approximately horizontal direction rearward inside the body of the keyboard musical instrument. Thus, the depth of the body of the keyboard musical instrument may be accordingly reduced.
In another aspect of the invention, there is provided a keyboard lid opening and closing mechanism for a keyboard musical instrument, wherein the rear lid is provided with rear lid projections extending in the lateral direction of the rear lid, and wherein the keyboard lid guide portion is provided with a lower groove wall and an upper groove wall approximately parallel with each other, the lower groove wall supporting the keyboard lid from thereunder through the rear lid projections when the rear lid moves between the lid closed position and the lid open position, and the upper groove wall preventing the keyboard lid from coming off to the upward direction through the rear lid projections when the rear lid moves between the lid closed position and the lid open position. This enables stabilized movement of the keyboard lid.
In this case, the rotation support portion includes the vicinity of the rear end of the lower groove wall, and a connecting groove wall connecting the rear end of the lower groove wall and the rear end of the upper groove wall. When the keyboard lid moves from the lid closed position to the lid open position, the rear lid projections of the rear lid abut the vicinity of the rear ends of the lower groove walls and the connecting groove walls, and the rear lid rotates around the rear lid projections. Therefore, the rear lid may be rotated smoothly.
The movement of the keyboard lid may be further stabilized according to the following keyboard lid opening and closing mechanism. In the mechanism, the front lid is provided with the front lid projections, and when the front lid moves between the lid closed position and the lid open position, the lower groove wall retains the front lid from thereunder through the front lid projection, while the upper groove wall prevents the front lid from coming off toward the upper direction through the front lid projections.
In a further aspect of the invention, there is provided a keyboard lid opening and closing mechanism for a keyboard musical instrument, wherein there are at least two rear lid projections, two of which extend coaxially toward opposite directions, and wherein there are at least two keyboard lid guide portions, two of which guide the coaxial two rear lid projections, respectively. With this mechanism, the position and the movement of the keyboard lid may be stabilized since the keyboard lid guide portions support and guide the keyboard lid from at least both sides of the keyboard lid.
In this case, easy attachment and detachment of the keyboard lid to and from the body of the keyboard musical instrument is facilitated when at least one of the coaxial two rear lid projections is configured to be extendable.
To attach the rear lid to the body of the keyboard musical instrument, an extendable one of the two coaxial rear lid projections is first shortened, and then the rear lid is moved such that the rear lid projections are positioned between the keyboard lid guide portions for guiding the rear lid projections, respectively. Then, the shortened rear lid projection is extended so as to make these rear lid projections be inserted between the two rear lid guide portions. By this, the keyboard lid is attached to the body of the keyboard musical instrument.
On the other hand, to detach the keyboard lid from the body of the keyboard musical instrument, an extendable rear lid projection is first shortened. This enables the two coaxial rear lid projections to be moved from between the two keyboard lid guide portions, and thus enables the rear lid to be detached from the body of the keyboard musical instrument.
In the event that the keyboard lid is not pushed straight when being housed inside the body of the keyboard musical instrument, forces of the same strength will not imposed on the both ends of the guide shaft, so that the keyboard lid may not be moved smoothly due to idling or slip of one of the both ends.
In a further aspect of the invention, there is provided a keyboard lid opening and closing mechanism for a keyboard musical instrument, wherein the keyboard lid is provided with a rotatable guide shaft having respective pinion gears in the vicinity of both ends thereof and disposed along a direction perpendicular to the moving direction thereof, and wherein a pair of racks are arranged so as to be engaged with the respective pinion gears when the keyboard lid moves between the lid closed position and the lid open position. This mechanism, in which the pinion gears at the both ends of the guide shaft and the racks are engaged with each other, will not cause the above mentioned idling or slip, so that the movement of the keyboard lid may be further stabilized.
In this case, a guide shaft provided with the rear lid projection at both ends thereof will simplify the structure of the mechanism.
Furthermore, the keyboard lid guide portion, the rack and the reverse V-shape forming portion, which are integrally configured and are attachable/detachable to/from the arm, can be easily attached to the arm with screws and the like. This may reduce the number of assembly steps of the entire keyboard musical instrument.